Adjusting and applying traction to a patient's arm

A surgical shoulder lift comprising:

• a hollow, curved boom having a first end and a second end, the hollow, curved boom defining an interior of the curved boom, a first opening leading to the interior of the curved boom being formed at the first end of the curved boom and a second opening leading to the interior of the curved boom being formed at the second end of the curved boom;
• a first pulley mounted proximately to the first end of the curved boom;
• a second pulley mounted proximately to the second end of the curved boom;
• a mounting assembly configured to latch onto a rail of an operating table and having a hollow columnar support, the hollow columnar support defining an interior of the columnar support that is configured to receive at least a portion of the second end of the curved boom and secure the curved boom within the columnar support;
• a tension slider ring wrapped around at least a portion of the circumference of the curved boom at a position along the curved boom that is between the first and second ends of the curved boom;
• a spring scale having a first end and a second end, the first end of the spring scale being coupled to the tension slider ring;
• and
• a cable having a first end and a second end, the cable running over the first pulley, through the first opening formed at the first end of the curved boom and the second opening formed at the second end of the curved boom such that the cable is threaded through the interior of the curved boom, and over the second pulley, the first end of the cable being configured to be coupled to an arm sleeve for holding a patient's arm and the second end of the cable being coupled to the second end of the spring scale, wherein the spring scale is configured to measure the force with which the cable pulls on the second end of the spring scale.